Sedation Flashcards
Propofol mechanism of action
low dose- potentiates Gaba
high dose- activates gaba receptors, slows dissociation of gaba from receptors
(slows the closing of calcium channels in the neuron)
which receptor does propofol bind to
GABA
Biggest contraindication of propofol
decreases preload, do not use for induction in pts with aortic stenosis
Effects of propofol (5)
resp. depression
hypotension
hyperlipidemia
hypertriglyceridemia
propofol infusion syndrome
4 signs of propofol infusion syndrome
bradycardic HF
lactic acidosis
rhabdomyolysis
acute renal failure
Properties of propofol
sedation an amnesic, no analgesia
Precedex mechanism of action
alpha-2 agonist
Precedex properties
sedative, amnesic, mild analgesia
Effects of precedex
hypotension
bradycardia
Contraindications of precedex
cardiac conduction defects
caution if HF or hemodynamic instability
How is propofol metabolized and excreted
hepatic metabolism
renally excreted
How is precedex metabolized and excreted
hepatic metabolism
renally excreted
Precedex half life
2-2.5 hours
How are opioids metabolized and excreted
hepatic metabolism
renally excreted
Fentanyl onset
1-2 minutes
Fentanyl lipid solubility
600x morphine
Lipid solubility meaning
drug must pass a lipid bilayer to enter the brain
Fentanyl two reasons it is safe
No histamine release
No active metabolites- no renal dose adjustment
Morphine onset
5-10 minutes
Morphine safety (4)
Histamine release causes hypotension
Active metabolites- requires 50% dose reduction in renal failure
Can cause seizures
No bronchoconstriction
Hydrocodone onset
5-15 mins
Hydrocodone safety (2)
No histamine release
Active metabolites- no need for renal dose adjustment
ketorolac mechanism of action
NSAID, inhibits prostaglandin
3 adverse effects of ketorolac
gastric mucosal injury
upper GI bleed
impaired renal function
ketorolac dose
30mg
tylenol mechanism of action
COX2 inhibition for pain
inhibits prostaglandin synthesis and release
Max dose tylenol
4grams/day
gabapentin mechanism
unknown
benzodiazepines metabolism and excretion
metabolized in liver
mostly renal excretion
4 properties of benzos
amnesic
anticonvulsant
promotes delirium
delayed awakening
versed onset and duration
rapid acting
2-5 mins
short duration
versed lipid solubility
high
versed continuous infusion considerations
limited to less than 48 hours d/t drug uptake into tissues
versed active metabolites?
active metabolites prolong sedation especially in renal failure
ativan duration
long acting, lasts 6 hours
max dose ativan and why
10mg/hr d/t propylene glycol used as solvent can lead to toxicity
why is propylene glycol toxic?
converts to lactic acid which leads to metabolic acidosis
propylene glycol toxicity s/sx (3)
delirium with hallucinations
hypotension
multisystem organ failure
benzo withdrawal syndrome (4)
agitation
disorientation
hallucinations
seizures
Rocuronium cisatracurium, and vecuronium mechanism of action
nicotinic-acetylcholine receptor antagonist at the muscle end-plate
Rocuronium duration (2)
intermediate acting
30 mins
how much of nAch needs to be blocked rocuronium
70% blocked
Rocuronium twitch goal
2-3
where are nAch receptors found
at neuromuscular junction
Rocuronium dose
0.6-1.2 mg/kg
Rocuronium metabolism
minimally, hepatic